Access point (AP) bad balancing mechanisms implemented by different vendors take into account the number of client devices associated to each AP as a key factor to determine whether there is any skew in the loads among different APs. However, the number of client devices alone does not always provide enough granularities for determining the bad of an AP, because some client devices could be silent, whereas other client devices could be doing large amount of data transfers across multiple sessions. Most of the conventional AP client bad balancing techniques focus on preventing an AP from getting into an uneven distribution of bad using, for example, the total number of associated client devices as a metric. Nevertheless, these AP client bad balancing techniques cannot solve the problem for an AP, which is handling more than its designed capacity.
In addition, no current AP load balancing technique looks into the nature of sessions currently in transit among the APs and client devices. Conventional client management techniques typically perform client steering only when the Signal-to-Noise Ratio (SNR) drops below a predetermined threshold value. If a client device continues to have good SNR, the client device will continue to be associated with the same AP. This is so even though the AP is overloaded with other client devices doing heavy data transfer, whereas at least one other adjacent AP is lightly loaded and can serve the client device's better.
Moreover, each AP may support multiple access categories, which include but are not limited to, voice, video, best effort, and background. In order for client devices to have a seamless wireless network experience, each AP is designed to support a maximum number of sessions for a particular access category. For example, when an AP is supporting 20 client devices with concurrent voice sessions, the client devices may experience increased latency, jitter, etc. Conventionally, call admission control (CAC) can be used to deny additional voice sessions when the AP is overloaded. However, there are at least two limitations to the CAC. First, CAC only applies to client devices running voice sessions, but does not apply to other client devices running video and/or unified communication sessions. Second, once a client device is already associated with an AP, the AP cannot deny the session anymore.